I have been working on the upper cowl lately in preparation of bonding the windshield in. I have wanted to have a small sub-panel mounted on top of the dash to house the Angle of Attack display so I cut a plug from Styrofoam and made the fiberglass fairing. I attached it to the upper cowl with brackets and mounted the display and compass in a flat aluminum panel.
The process took a long time and a bunch of head scratching to get it all covered in marine vinyl but it was very much worth the effort. Here are some photos of the finished product along with a laser-cut vent grill I designed for the two fans in the dash.
Hope you enjoy reading my blog. I’ll try to post more frequently.
I received this post on the Matronics RV-10 forum last night and it was a review of the RV-10 Axle Spacers. I was very pleased to receive the feedback from John Gonzales after he received his package in the mail from Cleaveland Tools. Here is what he wrote:
“Mine came in the mail today so I haven’t had the opportunity to install them yet, but positive comment is in order.
Not only are these stainless steel pieces milled extremely well, but the pre-load spacer’s tight tolerance and fit are very, very close. With no grease on the threaded spacer, it is beautiful to feel how the two parts fit (Glide) together. This is no cheap piece of hardware and they would more so belong on a very, very expensive telescope tripod or on tooling machinery. Better than anything the dental industry puts out.
Nice Job. Shame it is going to eventually get covered in grime.”
I think that I made the right decision to make these out of stainless steel and that I didn’t comprise on the design. Of the units I have sold, all have been happy with the quality and functionality.
This is a follow-up on what is happening with my axle spacers.
Cleaveland Tools and I have been contacting the people who expressed interest in my axle spacers to determine the true number of people interested in them after the Matco offering.
When I first found out about the Matco unit I really didn’t think that many of you would still be interested in my version. Thankfully that wasn’t true.
In the interim I have received a couple of direct orders from the States and a couple of orders from guys here in Canada. These plus the confirmations from Cleaveland have allowed me to put together a small production run to satisfy those who have stuck with my design.
I have the parts being manufactured as we speak and the Cleaveland units should be shipped to them within 2 weeks.
I hope to now keep the design on Cleaveland Tools catalog but I think it is going to be done on a pre-order basis.
I hope that this answers your question. If you have any more questions please do not hesitate to send them on.
Well I have received a couple of requests for my axle spacers even though the ones from Matco have been released. Thank you to those who like the design of my spacers over theirs. The comments that I have received are that customers want the stainless steel spacers I offer instead of the aluminum ones from Matco.
So here is what I am going to do. I am willing to produce these in small lots of 5 units and will put people on a waiting list until I get the 5 orders needed to manufacture them. This way I don’t have a whole lot of inventory sitting around.
I am also going to sell these units directly rather than through Cleaveland Tools. The numbers don’t make sense to have them keep stock.
I appreciate the trust that those who have purchased my products have put in me and I will continue to design high quality replacement parts and accessories for the kit aircraft market into the future.
It seems as though I have been scooped in the marketplace!!
With the introduction of the Matco adjustable axle my product offering has effectively been run outta town! There is little chance of me being able to compete with a product being offered by the company with whom the problem originated. This is just how things go sometimes.
I would like to inform those who had contacted Cleaveland Tools to place a pre-order that I have canceled the product offering in fairness to Mike at Cleaveland Tools even though they had ordered product already. I would hate to have that product sit on their shelves with no interest in them.
To those who had the confidence to pre-order my adjustable pre-load axle spacers, Thank You. It is always gratifying to have the confidence of your peers.
I look forward to offering other accessories and parts to the kit builder and kit manufacturer alike.
I’ve been working diligently in getting the axle spacer program up and running. Thanks to all of you who have come to read about them and who have gone to Cleaveland Tools and put your name on their waiting list. I will have product to them around the 15th of January.
I installed the prototypes on my nose gear today and took pictures to put together an informative instruction sheet. We got lots of good pictures and Mike Lauritsen is going to add them to his order page in the next couple of days.
I am hoping to get he word out to the RV-6/7/8/9 crowd that I have a fix for their problem design as well. It would be very helpful if any of you readers would mention it to your friends and possibly print out the article on my blog to post in your EAA, RAA, COPA and AOPA publications. Maybe even as an article in your newsletter.
The more people hear about this fix the more safe we are going to be. I have heard some real scarry stories about people coming back to land with excessive shimmy and spinning bearings.
I have been able to take the design for the RV-10 axle spacers and modify them to fit the RV-6, 7, 8 and 9A front wheel. They use the same bearing as the RV-10 and have been having the same problem with the spacers supplied by Van’s pre-loading on the bearing seal.
In this application, I reproduced the same configuration as the RV-10 including the through axle. I am going to be offering these two kits for sale through Cleaveland Aircraft Tools.
Retail price for the RV-10 will be around US$180.00 and the RV-6/7/8/9 will be around US$190.00 as the new axle is included. Cleaveland has not confirmed the final price but this is close. They will be available in January 2009.
The axle will be made of aluminum and will use the same through bolt that is supplied in the kit. The actual spacers will be made of stainless steel with stainless steel hardware. The locking screws that you tighten after adjusting the pre-load will have drilled heads so they can be safety wired. As well, there is a notch milled into the outer portion of the spacers that fit into the heads of two socket head cap screws. These screws are installed in the yoke and keep the spacers from rotating.
Here are some photos. Contact me at HERE or submit a comment if you are interested in purchasing these.
For some time now I have been hearing of problems intrinsic to Van’s front wheel design in that there have been instances of wheel shimmy and the loss of preload on the front wheel bearings. My investigation into the problem has led me in a couple of directions.
First, there is the issue of the bearings spinning on the axle and the subsequent damage that is caused to the yoke. Van’s has tried to fix the initial problem due to a spacer that was too thin. At 1/16″, the spacer would bite into the bearing race and start to spin on the axle shaft. The spacer would then start cutting into the aluminum yoke and all bearing preload would be lost. This results in front wheel shimmy and all of its inherent risks.
Van’s tried to fix the problem with a thicker spacer made of aluminum which was 1/4″ thick. This has lead to the second problem.
The thicker spacer now contacts and preloads on the seal of the bearing which is leading to seal breakdown and the resultant spinning of the spacer, galling of the yoke and ultimately seal separation from the bearing. I have seen this personally and it is quite disconcerting.
To understand this all we need to revert back to the design philosophy of the Matco wheel that Van’s uses in many of its home built kits. This wheel and bearing set-up requires a preload to be placed against the cone so that it stays seated in the cup and bears the load of the aircraft. When pre-load is lost for whatever reason the cone can come away from the cup slightly with the ramifications being wheel shimmy, bearing damage and ultimately bearing failure.
The wheel/bearing system from Matco is designed to operate in the following manner:
The bearings are made up from two parts called the cone and the cup. The cup is pressed into the wheel hub and the cone is forced against the cup by the sleeve that is installed between it and the yoke. In this design it is very important that the sleeves that provide the pre-load on the outer steel portion of the cone be of a specific length.
The axle that supports everything has to be just a little shorter than the sum of the wheel, bearings and sleeves so that when the outer bolts are tightened the axle does not mate to the yoke. This allows the compression forces to be placed against the outer portion of the sleeves. These compression forces constitute the pre-load that forces the cone to mate properly with the cup in the hub of the wheel. When looking at the wheel while it is spinning, theseal should be stationary.
Now the sleeves have to make good contact with the steel portion of the cone so that it is forced to remain stationary. Both the steel portion of the bearing and the seal should not rotate if the system is set up correctly. The fundamental problem we are seeing with this wheel/bearing/sleeve system is that the contact with the steel portion of the bearing is not being made correctly.
When the 1/4″ thick sleeve of Van’s is used it contacts the inner 1/16″ of the seal and not the steel portion of the bearing. With the preload on the rubber surface of the seal it deteriorated quickly and the proper preload on the bearing is lost. This sleeve needs to be 3/16″ thick to do the job properly.
Compounding this problem is the fact that the steel portion of the cone that the sleeve contacts is curved. It presents a challenge in transferring the compression force from the flat face of the sleeve to the curved face of the cone. The result of this is the propensity of the cone to spin on the axle. This in turn causes the sleeve to spin on the axle and damage the yoke.
Clear as mud I know but it is important to get technical in this explanation as there are many misconceptions out there right now.
Here is how I approached fixing the problem:
First there needed to be a way of getting a consistent preload on the bearing cone without relying on precise measurements in the length of the sleeves. To do this I proposed that an adjustable sleeve on one side of the wheel and a fixed-length sleeve on the other be employed. These sleeves have a profile cut into the face that contacts the cone that matches their radii. It is cut to the proper diameter so that no part of it can touch the seal rubber.
What this does is allow the axle to yoke joint to be more robust by having a properly torqued bolt on both sides. The adjustable sleeve is both a bolt and a nut with a hole through the bolt for the axle. The head of the bolt rests against the yoke and the nut rests against the outer steel face of the bearing cone. When you loosen the nut away from the bolt it tightens against the bearing and preloads it against the bearing cone. Once you attain the proper preload you simply tighten set screws to affix its preload.
A big bonus to this is that the preload can be set without taking the wheel off. This eases maintenance and allows for quicker adjustments.
The second area I tackled is that of the spacers spinning and causing damage to the inner part of the yoke. Here I decided to have a small round milled out of the flanges of the spacers where they contact the yoke. You measure out from the center of the front wheel bolt hole and drill a hole. You then tap it for a 10-24 socket head cap screw. This screw head nests into the milled half round in the flange to keep it from rotating.
Together, these two approaches should solve the problem with the seals being damaged and the loss of preload on the bearings.
I will be offering these for sale through Cleaveland Aircraft Tools and possibly through Van’s and Aircraft Spruce in the future.
I invite your comments and I will add pictures to this post a little later.
I saw that there was a listing today on eBay for an RV-10 that has a 600hp Corvette LS7 engine shoehorned into it. I went and saw the listing. What can I say. If this person has designed the firewall forward system in the same fashion as he has built the airframe then I hope he never sells the thing. Especially to someone who doesn’t know all of the facts. Someone bedazzled by the sexiness of having the Corvette emblem attached to the aircraft.
You can go to the listing here and have a look for yourself. I don’t know about you but I don’t think that the side skins of the RV-10 are attached with 1/8″ rivets. All of those clecos are supposed to be silver aren’t they? There’s a whole lot of head scratching going on here!!
I personally have looked long and hard into the Corvette conversion and have had extensive conversations with experts in the field. I even flew out to meet Jack Kane who owns EPI Inc. in Washington state. We looked at the many many many variables in converting an automotive engine to aircraft use and simply couldn’t make the math work out without making a whole slew of compromises. Jack is a pretty smart cookie with the degrees and experience to back up his opinions.
I tucked my tail between my legs and headed home. I will put it very simply. There are precious few alternatives currently available for the person building an RV-10 when it comes to an alternative to the venerable Lycosaurus. This is not to say that there aren’t some exiting developments in the works.
I am working on an engine project of my very own. One that uses a proprietary compressor/effector technology that has been developed by a company in Texas. It will use the Brayton cycle which is the same cycle used in turbine engines but it will use a different and more efficient compressor and effector than the axial turbines used today.
My primary goal is to have the new engine fit into the space that existing Lycoming takes up. No new cowl, no new engine mount. It will directly replace the Lycoming.
It will be able to burn almost any type of fuel. Gasolines, naptha, diesels, kerosenes and bio-fuels. The problem for me is that it is going to take a pretty big chunk of cash to make it happen.
Anyway, I digress. It is a wonderful thing that we can invent and implement these inventions within the framework of the experimental category. It is very important though that we do things in the safest and most professional way so that those who are building the plan-jane version are not adversely affected by the insurance industry and the relentless pursuit of the ambulance chasing lawyers.
I had a fellow in the yesterday having a look at the fiberglass parts that Van’s sends with their kits. This guy lives, eats and breathes everything composite. From America’s Cup boats to custom canoes for children. I have seen his work and I am glad that he came over.
When we had a moment to talk, he told me that Clamar Floats, whom he does a lot of work for is going to be installing a set of their beautiful composite floats on a Van’s RV-7. Talk about a conversation starter. Apparently this fellow lives in the Pacific northwest and is quite an accomplished float plane pilot.
This isn’t the first Van’s aircraft to receive the float treatment. A fellow from British Colombia installed a set a number of years ago and successfully flew them on a Van’s RV-6. His name was Eustace Bowhay. You can read about his installation by clicking here.
I don’t know about all of you out there but I think that I would have a bit of a hard time with the thought of having to extract my 6 foot 200 lb self out of the aircraft to dock the thing.
